Aion Theseus (KoT) issues

[RickMcCarthy]

Plenty of ways to speculate possibilities but it's easier just to check the 100uF polarity!

Yes, I did just quadruple check and C10 is not reversed. Strange as that was one of those things I first looked at. Frustrating and troubling, this is.

[Rob Strand]

Yes, I did just quadruple check and C10 is not reversed. Strange as that was one of those things I first looked at. Frustrating and troubling, this is.

And a little more frustrating that one identical channel is working.
You just have to keep at it.  Weird problems take a bit of perseverance.

What if you go back to basics.   Pull IC1 and measure the voltages on VB and also on the IC pins.

If nothing is wrong we would expect:
- VB 4.1V
- pin 8 8.2V
- pin 4 0V
- pin 5 same as VB
- pin 3 a little lower than VB

The more obscure voltages:
- pins 1 and 2  0V
- pin 6 and 7 should be a tiny bit below VB, with pin 7 being lower than R6.
  The voltages here pics up VB via a long path:
  Volume pot -> R10 -> Tone pot -> R9  to pin 7, then through R7 to pin 6

The small changes might not be visible on a 3.5 digit DMM with a 10M impedance.
Cheaper DMMs with 1M input impedance will show more deviations.
From your IC2 measurements I'm guessing your meter is 10M input impedance.

You could also check these voltages with the diode switch in different positions and the gain pot in different positions.
Check as much as you can.

[RickMcCarthy]

Yes, I did just quadruple check and C10 is not reversed. Strange as that was one of those things I first looked at. Frustrating and troubling, this is.

And a little more frustrating that one identical channel is working.
You just have to keep at it.  Weird problems take a bit of perseverance.

What if you go back to basics.   Pull IC1 and measure the voltages on VB and also on the IC pins.

If nothing is wrong we would expect:
- VB 4.1V
- pin 8 8.2V
- pin 4 0V
- pin 5 same as VB
- pin 3 a little lower than VB

The more obscure voltages:
- pins 1 and 2  0V
- pin 6 and 7 should be a tiny bit below VB, with pin 7 being lower than R6.
  The voltages here pics up VB via a long path:
  Volume pot -> R10 -> Tone pot -> R9  to pin 7, then through R7 to pin 6

Yes, I think a refreshed approach makes sense. Remember too that I had a broken trace on the footswitch board which I believe was due to a heavy hand on the iron. I might be into a new PCB before long.

The small changes might not be visible on a 3.5 digit DMM with a 10M impedance.
Cheaper DMMs with 1M input impedance will show more deviations.
From your IC2 measurements I'm guessing your meter is 10M input impedance.

You could also check these voltages with the diode switch in different positions and the gain pot in different positions.
Check as much as you can.

I think I know what this is. The earliest readings were take with my Fluke 767 Process Meter while I grabbed my cheap, old Radio Shack DVM for the later readings. Apologies as I should've pointed that out. Lost in my troubleshooting it had slipped my mind.

I'll try your suggestions later today. Thanks, Rob,

[Slowpoke101]

Sorry to jump in here Rob but I've got a few suggestions that may narrow down Rick's problem - or add to his confusion.

Set your meter to DC volts, connect the negative lead to 0V, power up the pedal and locate R12. Measure the voltages on each end of the resistor. One end should read about 8.5V and the other end about 4.3V hopefully. If you don't get these voltages look for damaged tracks and try to repair them. Now if all is good power the pedal down, remove the meter's negative lead from 0V and set the meter to continuity or low ohms.

See if there is continuity between the end of R12 that had 4.3V on it and the positive leg of C10 and pin 5 of IC1B. If there is a break in continuity look for board damage. If you cannot see any just simply install some insulated wire jumpers between these points.

Lastly, R1. One end of R1 connects to pin 3 of IC1. Use your meter's continuity test or low ohms to find which end of R1  connects there. Once found, check if the other end of R1 connects to the leg R12 that had 4.3V on it. If it doesn't connect then you have board damage and you need an insulated jumper but this jumper should go to C10 positive and not R12.

Some of these boards can be a little bit delicate and easy to damage. So be gentle with them. The dark solder masks also makes it difficult to see if damage has occurred. Just take your time.

Sorry for hijacking the thread Rob, I'll see myself out now. Cheers.

[Rob Strand]

Sorry for hijacking the thread Rob, I'll see myself out now. Cheers.

No problem at all.  I wish you did it more often!

[RickMcCarthy]

Sorry to jump in here Rob but I've got a few suggestions that may narrow down Rick's problem - or add to his confusion.

Set your meter to DC volts, connect the negative lead to 0V, power up the pedal and locate R12. Measure the voltages on each end of the resistor. One end should read about 8.5V and the other end about 4.3V hopefully.

I did this earlier an I did get those voltages. The voltage never did make it's way to + of C10, though.

If you don't get these voltages look for damaged tracks and try to repair them. Now if all is good power the pedal down, remove the meter's negative lead from 0V and set the meter to continuity or low ohms.

See if there is continuity between the end of R12 that had 4.3V on it and the positive leg of C10 and pin 5 of IC1B. If there is a break in continuity look for board damage. If you cannot see any just simply install some insulated wire jumpers between these points.

I jumped from R12 to C10 but left out jumping to IC1B. I will try that today.

Lastly, R1. One end of R1 connects to pin 3 of IC1. Use your meter's continuity test or low ohms to find which end of R1  connects there. Once found, check if the other end of R1 connects to the leg R12 that had 4.3V on it. If it doesn't connect then you have board damage and you need an insulated jumper but this jumper should go to C10 positive and not R12.

This is something I overlooked. I'll bet there is a break in here somewhere for sure.

Some of these boards can be a little bit delicate and easy to damage. So be gentle with them. The dark solder masks also makes it difficult to see if damage has occurred. Just take your time.

You are so right. Remember, I did get "A" side running by jumpering a broken trace to the VC pad on the footswitch board. I'm sure I was too heavy with the iron elsewhere. I'll continue with this board as not to admit defeat, but I'll also be ordering another board from Kevin and another bunch of parts. This will be a mess once it's up and running, so I'll build another one (more carefully) and give this one to a friend.

Sorry for hijacking the thread Rob, I'll see myself out now. Cheers.

I really appreciate all the help from all of you that have taken the time to comment. Thank you. I wish I jumped in and joined sooner.
Ok... I'll be back with some findings a little later today...

[RickMcCarthy]

See if there is continuity between the end of R12 that had 4.3V on it and the positive leg of C10 and pin 5 of IC1B. If there is a break in continuity look for board damage. If you cannot see any just simply install some insulated wire jumpers between these points.

Lastly, R1. One end of R1 connects to pin 3 of IC1. Use your meter's continuity test or low ohms to find which end of R1  connects there. Once found, check if the other end of R1 connects to the leg R12 that had 4.3V on it. If it doesn't connect then you have board damage and you need an insulated jumper but this jumper should go to C10 positive and not R12.

Lots of damaged traces in the suggested locations and a few I found, as well. So, I installed the following jumpers:

1) 4.3v side R12 to + pad C10
2) + pad C10 to IC1 pin 5
3) R1 to IC1 pin 3 (other end of R1 made contact to R12)
4) C2 to IC1 pin2 (now makes to R5, R2, IC- pin 2 and other end of C2 makes to IC1 pin 1 and Drive pot wiper)

Powered up and the jumpers pass voltage as they should. I now have the following readings (Fluke 787) all pots fully counterclockwise:

IC1

Pin 1: 1.32v
Pin 2: 2.61v
Pin 3: 4.04v
Pin 4: 0v
Pin 5: 4.23v
Pin 6: 4.24v
Pin 7: 4.22v
Pin 8: 8.54v

IC2

Pin 1: 4.26v
Pin 2: 4.28v
Pin 3: 4.27v
Pin 4: 0v
Pin 5: 3.97v
Pin 6: 4.36v
Pin 7: 4.35v
Pin 8: 8.55v

Supply: 9.02VDC

Could I have an open C2? Voltages on pins 1 & 2 are still not right and there is a bit of weirdness going on - when I test pins 1 or 2 from either IC my voltage will begin consistent, but then it drifts. Usually up to 8 1/2v on both pins, both ICs. I don't know why I have the drift on IC2 also, but I'll look into that a bit later. It's still early here so I'll have to wait a while before plugging it in and seeing what it passes for signal.

Let me ask you guys a practical question: how many jumpers is too many? Lol! I fully admit that I boogered up this board hastily soldering with my ancient (don't laugh) Radio Shack iron with a age broadened tip often after a long day at work or early in the morning. There might have been beer involved, as well. Lol.

I'll keep going on this to see it through and learn from it and you folks, but I think it might be time to order a new PCB and wait for the Amazon man with that new soldering station. I plan on having this pedal on my board and looking at all these jumpers doesn't have me brimming with road-worthy confidence.

[duck_arse]

some points of interest. what's happening with those white crescents? - the green arrows.
in the red circles are what looks like exposed copper, which suggests scrapes and broken tracks. anything looking like that needs inspection and repair.
the blue rings are unwetting joints - they look good, but the solder is intermittant at best, not making good solid joint with lead. there are probably others same ....

how many links? as many as needed is the right amount, more than that is too much. however, I'd say toast for that board. stick with it, get it right, but then build a new one.

[RickMcCarthy]

some points of interest. what's happening with those white crescents? - the green arrows.
in the red circles are what looks like exposed copper, which suggests scrapes and broken tracks. anything looking like that needs inspection and repair.
the blue rings are unwetting joints - they look good, but the solder is intermittant at best, not making good solid joint with lead. there are probably others same ....

Yes, those crescents are iron marks. Shame on me for not using a new, fine tip and that broad iron tip along with my hasty, ham-fisted ways caused some rubbing scoring on a delicate board - definitely compromised traces.

how many links? as many as needed is the right amount, more than that is too much. however, I'd say toast for that board. stick with it, get it right, but then build a new one.

I did order a new PCB from Aion today and I'll likely get a complete parts set as well. I am committed to getting this one running if only to pin it to the wall after to remind me to take my time and be more careful.
More hunting and pecking later today. Thank you duck_arse.

[Slowpoke101]

Those wire links have made a difference. Now with the voltages on pins 1 and 2 of IC1A you are going to have to check for more broken tracks or poorly soldered component leads. Many thanks to duck_arse for highlighting some of those. R2 is the one of most concern and its soldering could be better, sorry to say. Also, please try to obtain a more suitable soldering iron or a smaller tip at the very least. Also be careful of running the iron too hot.

Set your meter to continuity test or low ohms and make certain that the pedal is powered down. Turn the DRIVE_A control fully counter clockwise (CCW) - as if turning an amp control to zero. You will also need to find R2, R6 and C2. I'm not worried about other possible problems other than getting U1A's voltages correct so concentrate only on these components and their connections for the moment.

Check that there is continuity from pin 2 of IC1A to one leg of R2 and to one leg of C2. If you can't get any continuity to the IC, try to see if there is any between the components. Hopefully there will be and you can then run a link over the broken connection. If you look at the circuit diagram you can see that just one break in this area disconnects quite a few components and any, if not all, may no longer be connected to where they should be. Feel free to test.

Next. Test for continuity between R2 and Leg 1 of the DRIVE_A pot. If you are looking at the component side of the board, Leg 1 is the rightmost leg of the pot. Also Leg 3 (leftmost) goes to R6 and it would be a good idea to check that that connection has continuity too.

Lastly for this post we go back to IC1. Pin1 goes to Leg 2 (centre leg) of the DRIVE_A pot and one side of C2. Check the continuity of these connections and repair them if there's a problem.

Keep in mind that the King of Tone is just two Tube Screamers (with some additional features) in the one box so if one side is working you have that side to compare with against the non functioning side. This can be very helpful when chasing signals or voltages through the effect. It's a good pedal to have so don't give up on your build. It will be worth it in the long run.

[RickMcCarthy]

Those wire links have made a difference. Now with the voltages on pins 1 and 2 of IC1A you are going to have to check for more broken tracks or poorly soldered component leads. Many thanks to duck_arse for highlighting some of those. R2 is the one of most concern and its soldering could be better, sorry to say. Also, please try to obtain a more suitable soldering iron or a smaller tip at the very least. Also be careful of running the iron too hot.

Set your meter to continuity test or low ohms and make certain that the pedal is powered down. Turn the DRIVE_A control fully counter clockwise (CCW) - as if turning an amp control to zero. You will also need to find R2, R6 and C2. I'm not worried about other possible problems other than getting U1A's voltages correct so concentrate only on these components and their connections for the moment.

Check that there is continuity from pin 2 of IC1A to one leg of R2 and to one leg of C2. If you can't get any continuity to the IC, try to see if there is any between the components. Hopefully there will be and you can then run a link over the broken connection. If you look at the circuit diagram you can see that just one break in this area disconnects quite a few components and any, if not all, may no longer be connected to where they should be. Feel free to test.

Next. Test for continuity between R2 and Leg 1 of the DRIVE_A pot. If you are looking at the component side of the board, Leg 1 is the rightmost leg of the pot. Also Leg 3 (leftmost) goes to R6 and it would be a good idea to check that that connection has continuity too.

Lastly for this post we go back to IC1. Pin1 goes to Leg 2 (centre leg) of the DRIVE_A pot and one side of C2. Check the continuity of these connections and repair them if there's a problem.

Keep in mind that the King of Tone is just two Tube Screamers (with some additional features) in the one box so if one side is working you have that side to compare with against the non functioning side. This can be very helpful when chasing signals or voltages through the effect. It's a good pedal to have so don't give up on your build. It will be worth it in the long run.

Sorry for the late reply, but it's been a hectic week at work. Among the usual was a complete rewire on a 500 ton dryer's burner. Unlike my Theseus project, that fired up on the first try. Lol

All good suggestions there and I plan to dig in today and tomorrow. The new soldering station has arrived along with the new board and parts to build a new KoT. I'll get to deskldering and resoldering the 1st attempt and see what I can learn, though being careful with a new iron not running too hot will likely bear fruit. I'd still like to get this frankenjumpered version going as it will make a nice gift. At least to any guitarist friend who dare not peak under the hood. 

More soon!